In aircraft construction, components are required for a wide range of applications in safety-relevant areas, especially in the wings, which are fault-free and fail-safe or, in the event of damage, have replacement devices which, automatically recognizing the failure of the damaged part of the component, will automatically and safely replace it, i.e. the function of which must be designed according to the “fail-safe” principle. In this context, “fail-safe” means that the component in question contains at least two equivalent systems which can fulfill the specified task of the component, whereby only one of the two systems may ever come into play. If the first system fails, its function must be automatically taken over by the second system on an equivalent basis. It is particularly important here that the failure of the first system can be automatically detected and repaired by the component.
These requirements apply in particular for the push-pull rods which are frequently used in aircraft construction and which are subject to particular stress because of the strong and frequently changing loads, so that total failures as a result of material fatigue or overloading must be excluded.
At the moment, these requirements are met by the fact that, with frequent maintenance intervals, as a precaution after a defined period of use, the push-pull rods are routinely replaced or removed, disassembled, tested, re-assembled and re-installed which, however, naturally involves considerable effort and cost.
The push-pull rods that are common in particular in aircraft construction are available in various versions, such as those described, for example, in DE 202004016321. As a rule, these tubular single-wall bodies are made from light alloy, titanium or carbon-fiber reinforced plastic, provided at each end with a single-layer yoke or eye made from light alloy.